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基于高速风洞投放模型试验的经验,论述和总结了对试验技术的实际应用较为重要、且对试验结果有较大影响的几个关键问题:相似准则的选取问题、投放分离参数的模拟问题、风洞启动时流场对投放物模型的冲击载荷问题以及数据处理方法,分别对这四个问题的具体选取原则和处理方法进行了详细的总结和分析。重模型法能够确保模型投放轨迹的严格相似,但实用性较差;而轻模型法则正好相反。由于重模型法在实际使用中通常难以应用,因此轻模型法在风洞投放模型试验中获得了较多应用,但其模型垂直加速度不足的问题也需引起重视。投放分离参数的相似模拟,通常可通过采用弹簧或气缸提供的投放作用力来实现,弹簧具有简单、易行的特点,但模拟的准确性稍差;而气缸则正好相反。风洞启动时流场对投放物模型的冲击载荷问题常常能够影响到试验的顺利进行或影响试验结果。数据平滑处理可采用时间多项式拟合来实现,进而通过一次或二次微分获得气动力系数。对高速风洞模型投放试验的应用领域作了总结和介绍,将其分为飞机外挂物/内埋武器投放、子母弹抛撒/重块抛撒,以及头罩/导弹壳片分离三大类型试验,并对每一类试验在具体的试验技术,以及在上述几个关键问题上的特点分别作了介绍,给出了具体试验的图像和曲线。
Based on the experience of high-speed wind tunnel deployment model test, several key issues that are important to the practical application of the test technology and have a great impact on the test results are discussed and discussed: the selection of similarity criteria, the simulation of running separation parameters, When the wind tunnel is started, the flow field affects the impact load of the delivery model and the data processing method, and the specific selection principles and handling methods of these four problems are summarized and analyzed in detail. The heavy model method can ensure the exact similarity of the trajectory of the model, but the practicality is poor, while the light model is just the opposite. Due to the fact that the heavy model method is usually difficult to be applied in practical applications, the light model method has gained more applications in wind tunnel casting model tests. However, the problem of insufficient vertical acceleration of models also needs attention. Similar simulations of the release of discrete parameters can usually be achieved by using spring or cylinder delivery forces. The spring is simple and easy to implement, but the simulation is somewhat less accurate; the cylinder is the opposite. The impact loading problem of the flow field on the delivery object model when the wind tunnel is started can often affect the smooth running of the test or affect the test result. The data smoothing can be achieved by time polynomial fitting, and the aerodynamic coefficient can be obtained by one or two differentials. This paper summarizes and introduces the application field of the high-speed wind tunnel model test, and divides it into three types of tests: aircraft plug-in / embedded weapon deployment, bullet scatter / weight scatter, and hood / missile shell separation For each type of test in the specific test techniques, as well as in the above several key issues on the characteristics were introduced, given the specific test images and curves.